Bulgaria’s only nuclear power plant, Kozloduy, has announced another shutdown of its 1,000 MW Unit 6, which is scheduled to go offline on 22 December after a malfunction was detected in a safety-related component of the turbine system.
The issue emerged while the reactor was in operation and affects the protective membrane of the steam superheater separator, a component located outside the nuclear island. Earlier this month, on 15 December, Unit 6 had already been taken out of service to replace a similar protective device and was only briefly returned to operation.
Plant management confirmed that replacement parts are available on site. Prior to installation, the spare components will undergo independent external inspections and testing. All repair activities will be conducted in line with established technical maintenance procedures and strict quality control standards.
Kozloduy officials emphasized that the steam release associated with the malfunction poses no environmental risk. The steam consists exclusively of treated water from the turbine system and originates from the conventional section of the unit, with no link to nuclear processes and no release of harmful substances.
Following completion of the repairs and the necessary verification procedures, Unit 6 is expected to be reconnected to Bulgaria’s national electricity grid. In the meantime, Unit 5 continues to operate normally and remains unaffected by the incident.












